I have done two rv delam repairs. The first was on a friends Itasca which had separated around a large window all the way down to the bottom, about an 7' x 5' area to repair. The second was on my Winnebago which had separated around the fuel filler to the bottom of the panel about a 3' x 2' area to repair. I have used epoxies and resins through out my carpentry career and as an amateur boat builder and restorer.
I got some advice from a supplier(Merton's, Springfield MA) who suggested I use a pre- thickened epoxy (bar top epoxy) It is cheaper than using West 105 and cabosil and is more than adequate strength for the task. I modified a caulking tube and added a small section of plastic tubing connected to a piece of 4 mm steel brake line to deliver the epoxy where it was needed and then used a laminate roller to make sure the epoxy was forced through all the veneer layers saturating them and to keep it from pooling. Since the weather was a warm 75 deg on the day I did the repair on my Winnebago. I refrigerated the epoxy down to 60 degrees prior to mixing to extend the working time to 1 hour.
Clamping needs to be figured out ahead of time. I placed all the clamps, pads and braces ahead of time and then marked and photographed them so I could quickly put them back on before the epoxy began pooling or curing. I left the clamps on for 24 hours. In the picture below the repair was done in two stages. The first was the bottom as pictured. The second day I repaired the area around the filler neck cut-out and down to the first day first repair. I also carefully sealed and doubled coated the area inside the opening which was the source of the water intrusion.